Note: Poor performance of an automatic transmission can be mainly caused by five reasons: poor engine performance, poor adjustments, hydraulic failures, mechanical failures, and computer malfunctions. Diagnostics should always begin with monitoring the fluid level and its condition (see chapter 1), systems of rods and their adjustments. After checking the adjustments, carry out a test drive to determine the need for further work to be carried out at the service station.
Primary control
1. Warm up the box to operating temperature.
2. Check the oil level in the box (see chapter 1).
- A) if the level is low, add oil;
- b) if the level is high, drain the excess, check the drained liquid for the presence of water. The presence of water in the box oil indicates a malfunction of the radiator walls (see chapter 3);
- V) if the oil is foamy, drain it and fill the box with fresh oil. Check that there is no water in the oil.
3. Adjust the engine idle speed.
4. Check the valve cable for free movement. Adjust cable if necessary (see Section 3). Check the ease of movement of the cable only on a warm engine.
5. Check shift cable (see Section 4). Make sure it is properly adjusted and the tie rods work smoothly.
Oil Leak Diagnosis
6. Most leaks are easily identified visually. Repair usually consists of replacing seals and gaskets. If leaks are difficult to detect, follow these tips.
7. Remember that automatic transmission oil is usually red. The use of engine oil is not allowed.
8. Drive the car for several kilometers. Place a large, clean piece of cardboard under the car. After one or two minutes, you should be able to see where the leaks are from the prints on the cardboard.
9. Carefully inspect the suspected leak.
10. If a leak is still not found, thoroughly rinse and dry surfaces.
11. Drive a few kilometers again to warm up the box and repeat the search procedure.
12. Once the leak is located, determine the cause of the leak and fix it: for example, if a flange is bent, installing a new gasket will not help.
Leaks through gaskets
13. Periodically inspect the oil pan. Make sure the bolts are tight and the gasket is in good condition.
14. Causes of leakage through the sump gasket: high oil level, high oil pressure, clogged ventilation hole, overtightened sump mounting bolts, buckling of the sump flange, damaged drive axle connection surfaces, damaged gasket. If a sealant was used instead of a gasket and there is an oil leak, then this type of sealant is not suitable.
Leaks through seals
15. Seal leaks are usually caused by too high an oil level or oil pressure, a blockage in the vent, a damaged seal seat, or improper installation. The shaft sealing surface may be damaged or the bearings may be damaged, resulting in excessive relative movement of the shaft and stuffing box.
16. Check that the dipstick tube is well seated and that the seal is on the dipstick cap. Periodically inspect the area around the speedometer drive mount and sensors.
Leaks in the hull
17. If there are leaks in the body, then there are pores or cracks in the casting - repair or replacement is required.
18. Be convinced of integrity of hoses and places of their connections on a box and a radiator.
Fluid leaking through vent and fill pipe
19. If this defect occurs, then it is due to the ingress of engine coolant, improper flogging of the box ventilation system and drain holes.